This invention relates to electromagnetically driven shutters and, particularly, to a simple shutter arrangement capable of producing a timing signal during a predetermined phase of the exposure process.
Conventional camera shutters generally utilize springs or the like for driving the shutter blades. Recently, various types of electromagnetically driven shutters have been proposed to cut the manufacturing cost of the camera mechanism, to simplify it, and make it more compact. Such electromagnetically driven shutters also lighten the camera, but have the disadvantage of making it difficult to obtain a powerful enough driving force because of the compact, small capacity, battery which must normally be used with a camera. Consequently, where a synchronizing switch is needed to operate a flash, a problem arises. This is so because a conventional spring drive system is sufficiently strong so that the power lost in driving the synchronizing switch contacts is negligible. However, operation of synchronizing contacts with an electromagnetically driven shutter can interfere with the running of the shutter blades. The effect of the switch on the blades is too significant to be disregarded.